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Why does this incredibly simple Makefile produce so many debugging protocols?

I am studying a Makefile and decided to write my first exercise. I have a directory with two files:

Makefile  makefile.cpp

Here is makefile.cpp (unexpected surprise!):

#include <iostream>

int main() {
  std::cout << "Hello World!\n";
  return 0;
}

And here is the Makefile:

CC = g++
FILES = makefile.cpp
OUT_EXE = makefileout

build: $(FILES)
    $(CC) -o $(OUT_EXE) $(FILES)

And then I ran make -d and got a very long log:

$ make -d
GNU Make 3.81
Copyright (C) 2006 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.
There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A
PARTICULAR PURPOSE.

This program built for x86_64-pc-linux-gnu
Reading makefiles ...
Reading makefile `Makefile '...
Updating makefiles ....
 Considering target file `Makefile '.
  Looking for an implicit rule for `Makefile '.
  Trying pattern rule with stem `Makefile '.
  Trying implicit prerequisite `Makefile.o'.
  Trying pattern rule with stem `Makefile'.
  Trying implicit prerequisite `Makefile.c'.
  Trying pattern rule with stem `Makefile'.
  Trying implicit prerequisite `Makefile.cc'.
  Trying pattern rule with stem `Makefile'.
  Trying implicit prerequisite `Makefile.C'.
  Trying pattern rule with stem `Makefile'.
  Trying implicit prerequisite `Makefile.cpp'.
  Trying pattern rule with stem `Makefile'.
  Trying implicit prerequisite `Makefile.p'.
  Trying pattern rule with stem `Makefile'.
  Trying implicit prerequisite `Makefile.f'.
  Trying pattern rule with stem `Makefile'.
  Trying implicit prerequisite `Makefile.F'.
  Trying pattern rule with stem `Makefile'.
  Trying implicit prerequisite `Makefile.r'.
  Trying pattern rule with stem `Makefile'.
  Trying implicit prerequisite `Makefile.s'.
  Trying pattern rule with stem `Makefile'.
  Trying implicit prerequisite `Makefile.S'.
  Trying pattern rule with stem `Makefile'.
  Trying implicit prerequisite `Makefile.mod'.
  Trying pattern rule with stem `Makefile'.
  Trying implicit prerequisite `Makefile.sh'.
  Trying pattern rule with stem `Makefile'.
  Trying implicit prerequisite `Makefile,v'.
  Trying pattern rule with stem `Makefile'.
  Trying implicit prerequisite `RCS/Makefile,v'.
  Trying pattern rule with stem `Makefile'.
  Trying implicit prerequisite `RCS/Makefile'.
  Trying pattern rule with stem `Makefile'.
  Trying implicit prerequisite `s.Makefile'.
  Trying pattern rule with stem `Makefile'.
  Trying implicit prerequisite `SCCS/s.Makefile'.
  Trying pattern rule with stem `Makefile'.
  Trying implicit prerequisite `Makefile.o'.
  Looking for a rule with intermediate file `Makefile.o'.
   Avoiding implicit rule recursion.
   Trying pattern rule with stem `Makefile'.
   Trying implicit prerequisite `Makefile.c'.
   Trying pattern rule with stem `Makefile'.
   Trying implicit prerequisite `Makefile.cc'.
   Trying pattern rule with stem `Makefile'.
   Trying implicit prerequisite `Makefile.C'.
   Trying pattern rule with stem `Makefile'.
   Trying implicit prerequisite `Makefile.cpp'.
   Trying pattern rule with stem `Makefile'.
   Trying implicit prerequisite `Makefile.p'.
   Trying pattern rule with stem `Makefile'.
   Trying implicit prerequisite `Makefile.f'.
   Trying pattern rule with stem `Makefile'.
   Trying implicit prerequisite `Makefile.F'.
   Trying pattern rule with stem `Makefile'.
   Trying implicit prerequisite `Makefile.r'.
   Trying pattern rule with stem `Makefile'.
   Trying implicit prerequisite `Makefile.s'.
   Trying pattern rule with stem `Makefile'.
   Trying implicit prerequisite `Makefile.S'.
   Trying pattern rule with stem `Makefile'.
   Trying implicit prerequisite `Makefile.mod'.
   Trying pattern rule with stem `Makefile.o'.
   Trying implicit prerequisite `Makefile.o,v'.
   Trying pattern rule with stem `Makefile.o'.
   Trying implicit prerequisite `RCS/Makefile.o,v'.
   Trying pattern rule with stem `Makefile.o'.
   Trying implicit prerequisite `RCS/Makefile.o'.
   Trying pattern rule with stem `Makefile.o'.
   Trying implicit prerequisite `s.Makefile.o'.
   Trying pattern rule with stem `Makefile.o'.
   Trying implicit prerequisite `SCCS/s.Makefile.o'.
   Trying pattern rule with stem `Makefile'.
   Trying implicit prerequisite `Makefile.c'.
   Looking for a rule with intermediate file `Makefile.c'.
    Avoiding implicit rule recursion.
    Avoiding implicit rule recursion.
    Trying pattern rule with stem `Makefile'.
    Trying implicit prerequisite `Makefile.y'.
    Trying pattern rule with stem `Makefile'.
    Trying implicit prerequisite `Makefile.l'.
    Trying pattern rule with stem `Makefile'.
    Trying implicit prerequisite `Makefile.w'.
    Trying pattern rule with stem `Makefile'.
    Trying implicit prerequisite `Makefile.w'.
    Trying pattern rule with stem `Makefile.c'.
    Trying implicit prerequisite `Makefile.c,v'.
    Trying pattern rule with stem `Makefile.c'.
    Trying implicit prerequisite `RCS/Makefile.c,v'.
    Trying pattern rule with stem `Makefile.c'.
    Trying implicit prerequisite `RCS/Makefile.c'.
    Trying pattern rule with stem `Makefile.c'.
    Trying implicit prerequisite `s.Makefile.c'.
    Trying pattern rule with stem `Makefile.c'.
    Trying implicit prerequisite `SCCS/s.Makefile.c'.
    Trying pattern rule with stem `Makefile'.
    Trying implicit prerequisite `Makefile.y'.
    Looking for a rule with intermediate file `Makefile.y'.
     Avoiding implicit rule recursion.
     Avoiding implicit rule recursion.
     Avoiding implicit rule recursion.
     Trying pattern rule with stem `Makefile.y'.
     Trying implicit prerequisite `Makefile.y,v'.
     Trying pattern rule with stem `Makefile.y'.
     Trying implicit prerequisite `RCS/Makefile.y,v'.
     Trying pattern rule with stem `Makefile.y'.
     Trying implicit prerequisite `RCS/Makefile.y'.
     Trying pattern rule with stem `Makefile.y'.
     Trying implicit prerequisite `s.Makefile.y'.
     Trying pattern rule with stem `Makefile.y'.
     Trying implicit prerequisite `SCCS/s.Makefile.y'.
    Trying pattern rule with stem `Makefile'.
    Trying implicit prerequisite `Makefile.l'.
    Looking for a rule with intermediate file `Makefile.l'.
     Avoiding implicit rule recursion.
     Avoiding implicit rule recursion.
     Avoiding implicit rule recursion.
     Trying pattern rule with stem `Makefile.l'.
     Trying implicit prerequisite `Makefile.l,v'.
     Trying pattern rule with stem `Makefile.l'.
     Trying implicit prerequisite `RCS/Makefile.l,v'.
     Trying pattern rule with stem `Makefile.l'.
     Trying implicit prerequisite `RCS/Makefile.l'.
     Trying pattern rule with stem `Makefile.l'.
     Trying implicit prerequisite `s.Makefile.l'.
     Trying pattern rule with stem `Makefile.l'.
     Trying implicit prerequisite `SCCS/s.Makefile.l'.
    Trying pattern rule with stem `Makefile'.
    Trying implicit prerequisite `Makefile.w'.
    Looking for a rule with intermediate file `Makefile.w'.
     Avoiding implicit rule recursion.
     Avoiding implicit rule recursion.
     Avoiding implicit rule recursion.
     Trying pattern rule with stem `Makefile.w'.
     Trying implicit prerequisite `Makefile.w,v'.
     Trying pattern rule with stem `Makefile.w'.
     Trying implicit prerequisite `RCS/Makefile.w,v'.
     Trying pattern rule with stem `Makefile.w'.
     Trying implicit prerequisite `RCS/Makefile.w'.
     Trying pattern rule with stem `Makefile.w'.
     Trying implicit prerequisite `s.Makefile.w'.
     Trying pattern rule with stem `Makefile.w'.
     Trying implicit prerequisite `SCCS/s.Makefile.w'.
    Trying pattern rule with stem `Makefile'.
    Rejecting impossible implicit prerequisite `Makefile.w'.
   Trying pattern rule with stem `Makefile'.
   Trying implicit prerequisite `Makefile.cc'.
   Looking for a rule with intermediate file `Makefile.cc'.
    Avoiding implicit rule recursion.
    Avoiding implicit rule recursion.
    Trying pattern rule with stem `Makefile.cc'.
    Trying implicit prerequisite `Makefile.cc,v'.
    Trying pattern rule with stem `Makefile.cc'.
    Trying implicit prerequisite `RCS/Makefile.cc,v'.
    Trying pattern rule with stem `Makefile.cc'.
    Trying implicit prerequisite `RCS/Makefile.cc'.
    Trying pattern rule with stem `Makefile.cc'.
    Trying implicit prerequisite `s.Makefile.cc'.
    Trying pattern rule with stem `Makefile.cc'.
    Trying implicit prerequisite `SCCS/s.Makefile.cc'.
   Trying pattern rule with stem `Makefile'.
   Trying implicit prerequisite `Makefile.C'.
   Looking for a rule with intermediate file `Makefile.C'.
    Avoiding implicit rule recursion.
    Avoiding implicit rule recursion.
    Trying pattern rule with stem `Makefile.C'.
    Trying implicit prerequisite `Makefile.C,v'.
    Trying pattern rule with stem `Makefile.C'.
    Trying implicit prerequisite `RCS/Makefile.C,v'.
    Trying pattern rule with stem `Makefile.C'.
    Trying implicit prerequisite `RCS/Makefile.C'.
    Trying pattern rule with stem `Makefile.C'.
    Trying implicit prerequisite `s.Makefile.C'.
    Trying pattern rule with stem `Makefile.C'.
    Trying implicit prerequisite `SCCS/s.Makefile.C'.
   Trying pattern rule with stem `Makefile'.
   Trying implicit prerequisite `Makefile.cpp'.
   Looking for a rule with intermediate file `Makefile.cpp'.
    Avoiding implicit rule recursion.
    Avoiding implicit rule recursion.
    Trying pattern rule with stem `Makefile.cpp'.
    Trying implicit prerequisite `Makefile.cpp,v'.
    Trying pattern rule with stem `Makefile.cpp'.
    Trying implicit prerequisite `RCS/Makefile.cpp,v'.
    Trying pattern rule with stem `Makefile.cpp'.
    Trying implicit prerequisite `RCS/Makefile.cpp'.
    Trying pattern rule with stem `Makefile.cpp'.
    Trying implicit prerequisite `s.Makefile.cpp'.
    Trying pattern rule with stem `Makefile.cpp'.
    Trying implicit prerequisite `SCCS/s.Makefile.cpp'.
   Trying pattern rule with stem `Makefile'.
   Trying implicit prerequisite `Makefile.p'.
   Looking for a rule with intermediate file `Makefile.p'.
    Avoiding implicit rule recursion.
    Avoiding implicit rule recursion.
    Trying pattern rule with stem `Makefile'.
    Trying implicit prerequisite `Makefile.web'.
    Trying pattern rule with stem `Makefile.p'.
    Trying implicit prerequisite `Makefile.p,v'.
    Trying pattern rule with stem `Makefile.p'.
    Trying implicit prerequisite `RCS/Makefile.p,v'.
    Trying pattern rule with stem `Makefile.p'.
    Trying implicit prerequisite `RCS/Makefile.p'.
    Trying pattern rule with stem `Makefile.p'.
    Trying implicit prerequisite `s.Makefile.p'.
    Trying pattern rule with stem `Makefile.p'.
    Trying implicit prerequisite `SCCS/s.Makefile.p'.
    Trying pattern rule with stem `Makefile'.
    Trying implicit prerequisite `Makefile.web'.
    Looking for a rule with intermediate file `Makefile.web'.
     Avoiding implicit rule recursion.
     Avoiding implicit rule recursion.
     Avoiding implicit rule recursion.
     Trying pattern rule with stem `Makefile.web'.
     Trying implicit prerequisite `Makefile.web,v'.
     Trying pattern rule with stem `Makefile.web'.
     Trying implicit prerequisite `RCS/Makefile.web,v'.
     Trying pattern rule with stem `Makefile.web'.
     Trying implicit prerequisite `RCS/Makefile.web'.
     Trying pattern rule with stem `Makefile.web'.
     Trying implicit prerequisite `s.Makefile.web'.
     Trying pattern rule with stem `Makefile.web'.
     Trying implicit prerequisite `SCCS/s.Makefile.web'.
   Trying pattern rule with stem `Makefile'.
   Trying implicit prerequisite `Makefile.f'.
   Looking for a rule with intermediate file `Makefile.f'.
    Avoiding implicit rule recursion.
    Avoiding implicit rule recursion.
    Trying pattern rule with stem `Makefile'.
    Trying implicit prerequisite `Makefile.F'.
    Trying pattern rule with stem `Makefile'.
    Trying implicit prerequisite `Makefile.r'.
    Trying pattern rule with stem `Makefile.f'.
    Trying implicit prerequisite `Makefile.f,v'.
    Trying pattern rule with stem `Makefile.f'.
    Trying implicit prerequisite `RCS/Makefile.f,v'.
    Trying pattern rule with stem `Makefile.f'.
    Trying implicit prerequisite `RCS/Makefile.f'.
    Trying pattern rule with stem `Makefile.f'.
    Trying implicit prerequisite `s.Makefile.f'.
    Trying pattern rule with stem `Makefile.f'.
    Trying implicit prerequisite `SCCS/s.Makefile.f'.
    Trying pattern rule with stem `Makefile'.
    Trying implicit prerequisite `Makefile.F'.
    Looking for a rule with intermediate file `Makefile.F'.
     Avoiding implicit rule recursion.
     Avoiding implicit rule recursion.
     Avoiding implicit rule recursion.
     Trying pattern rule with stem `Makefile.F'.
     Trying implicit prerequisite `Makefile.F,v'.
     Trying pattern rule with stem `Makefile.F'.
     Trying implicit prerequisite `RCS/Makefile.F,v'.
     Trying pattern rule with stem `Makefile.F'.
     Trying implicit prerequisite `RCS/Makefile.F'.
     Trying pattern rule with stem `Makefile.F'.
     Trying implicit prerequisite `s.Makefile.F'.
     Trying pattern rule with stem `Makefile.F'.
     Trying implicit prerequisite `SCCS/s.Makefile.F'.
    Trying pattern rule with stem `Makefile'.
    Trying implicit prerequisite `Makefile.r'.
    Looking for a rule with intermediate file `Makefile.r'.
     Avoiding implicit rule recursion.
     Avoiding implicit rule recursion.
     Avoiding implicit rule recursion.
     Trying pattern rule with stem `Makefile'.
     Rejecting impossible implicit prerequisite `Makefile.l'.
     Trying pattern rule with stem `Makefile.r'.
     Trying implicit prerequisite `Makefile.r,v'.
     Trying pattern rule with stem `Makefile.r'.
     Trying implicit prerequisite `RCS/Makefile.r,v'.
     Trying pattern rule with stem `Makefile.r'.
     Trying implicit prerequisite `RCS/Makefile.r'.
     Trying pattern rule with stem `Makefile.r'.
     Trying implicit prerequisite `s.Makefile.r'.
     Trying pattern rule with stem `Makefile.r'.
     Trying implicit prerequisite `SCCS/s.Makefile.r'.
   Trying pattern rule with stem `Makefile'.
   Rejecting impossible implicit prerequisite `Makefile.F'.
   Trying pattern rule with stem `Makefile'.
   Rejecting impossible implicit prerequisite `Makefile.r'.
   Trying pattern rule with stem `Makefile'.
   Trying implicit prerequisite `Makefile.s'.
   Looking for a rule with intermediate file `Makefile.s'.
    Avoiding implicit rule recursion.
    Avoiding implicit rule recursion.
    Trying pattern rule with stem `Makefile'.
    Trying implicit prerequisite `Makefile.S'.
    Trying pattern rule with stem `Makefile.s'.
    Trying implicit prerequisite `Makefile.s,v'.
    Trying pattern rule with stem `Makefile.s'.
    Trying implicit prerequisite `RCS/Makefile.s,v'.
    Trying pattern rule with stem `Makefile.s'.
    Trying implicit prerequisite `RCS/Makefile.s'.
    Trying pattern rule with stem `Makefile.s'.
    Trying implicit prerequisite `s.Makefile.s'.
    Trying pattern rule with stem `Makefile.s'.
    Trying implicit prerequisite `SCCS/s.Makefile.s'.
    Trying pattern rule with stem `Makefile'.
    Trying implicit prerequisite `Makefile.S'.
    Looking for a rule with intermediate file `Makefile.S'.
     Avoiding implicit rule recursion.
     Avoiding implicit rule recursion.
     Avoiding implicit rule recursion.
     Trying pattern rule with stem `Makefile.S'.
     Trying implicit prerequisite `Makefile.S,v'.
     Trying pattern rule with stem `Makefile.S'.
     Trying implicit prerequisite `RCS/Makefile.S,v'.
     Trying pattern rule with stem `Makefile.S'.
     Trying implicit prerequisite `RCS/Makefile.S'.
     Trying pattern rule with stem `Makefile.S'.
     Trying implicit prerequisite `s.Makefile.S'.
     Trying pattern rule with stem `Makefile.S'.
     Trying implicit prerequisite `SCCS/s.Makefile.S'.
   Trying pattern rule with stem `Makefile'.
   Rejecting impossible implicit prerequisite `Makefile.S'.
   Trying pattern rule with stem `Makefile'.
   Trying implicit prerequisite `Makefile.mod'.
   Looking for a rule with intermediate file `Makefile.mod'.
    Avoiding implicit rule recursion.
    Avoiding implicit rule recursion.
    Trying pattern rule with stem `Makefile.mod'.
    Trying implicit prerequisite `Makefile.mod,v'.
    Trying pattern rule with stem `Makefile.mod'.
    Trying implicit prerequisite `RCS/Makefile.mod,v'.
    Trying pattern rule with stem `Makefile.mod'.
    Trying implicit prerequisite `RCS/Makefile.mod'.
    Trying pattern rule with stem `Makefile.mod'.
    Trying implicit prerequisite `s.Makefile.mod'.
    Trying pattern rule with stem `Makefile.mod'.
    Trying implicit prerequisite `SCCS/s.Makefile.mod'.
  Trying pattern rule with stem `Makefile'.
  Rejecting impossible implicit prerequisite `Makefile.c'.
  Trying pattern rule with stem `Makefile'.
  Rejecting impossible implicit prerequisite `Makefile.cc'.
  Trying pattern rule with stem `Makefile'.
  Rejecting impossible implicit prerequisite `Makefile.C'.
  Trying pattern rule with stem `Makefile'.
  Rejecting impossible implicit prerequisite `Makefile.cpp'.
  Trying pattern rule with stem `Makefile'.
  Rejecting impossible implicit prerequisite `Makefile.p'.
  Trying pattern rule with stem `Makefile'.
  Rejecting impossible implicit prerequisite `Makefile.f'.
  Trying pattern rule with stem `Makefile'.
  Rejecting impossible implicit prerequisite `Makefile.F'.
  Trying pattern rule with stem `Makefile'.
  Rejecting impossible implicit prerequisite `Makefile.r'.
  Trying pattern rule with stem `Makefile'.
  Rejecting impossible implicit prerequisite `Makefile.s'.
  Trying pattern rule with stem `Makefile'.
  Rejecting impossible implicit prerequisite `Makefile.S'.
  Trying pattern rule with stem `Makefile'.
  Rejecting impossible implicit prerequisite `Makefile.mod'.
  Trying pattern rule with stem `Makefile'.
  Trying implicit prerequisite `Makefile.sh'.
  Looking for a rule with intermediate file `Makefile.sh'.
   Avoiding implicit rule recursion.
   Trying pattern rule with stem `Makefile.sh'.
   Trying implicit prerequisite `Makefile.sh,v'.
   Trying pattern rule with stem `Makefile.sh'.
   Trying implicit prerequisite `RCS/Makefile.sh,v'.
   Trying pattern rule with stem `Makefile.sh'.
   Trying implicit prerequisite `RCS/Makefile.sh'.
   Trying pattern rule with stem `Makefile.sh'.
   Trying implicit prerequisite `s.Makefile.sh'.
   Trying pattern rule with stem `Makefile.sh'.
   Trying implicit prerequisite `SCCS/s.Makefile.sh'.
  No implicit rule found for `Makefile'.
  Finished prerequisites of target file `Makefile'.
 No need to remake target `Makefile'.
Updating goal targets....
Considering target file `build'.
 File `build' does not exist.
  Considering target file `makefile.cpp'.
   Looking for an implicit rule for `makefile.cpp'.
   Trying pattern rule with stem `makefile.cpp'.
   Trying implicit prerequisite `makefile.cpp,v'.
   Trying pattern rule with stem `makefile.cpp'.
   Trying implicit prerequisite `RCS/makefile.cpp,v'.
   Trying pattern rule with stem `makefile.cpp'.
   Trying implicit prerequisite `RCS/makefile.cpp'.
   Trying pattern rule with stem `makefile.cpp'.
   Trying implicit prerequisite `s.makefile.cpp'.
   Trying pattern rule with stem `makefile.cpp'.
   Trying implicit prerequisite `SCCS/s.makefile.cpp'.
   No implicit rule found for `makefile.cpp'.
   Finished prerequisites of target file `makefile.cpp'.
  No need to remake target `makefile.cpp'.
 Finished prerequisites of target file `build'.
Must remake target `build'.
g++ -o makefileout makefile.cpp
Putting child 0x01a6de60 (build) PID 6157 on the chain.
Live child 0x01a6de60 (build) PID 6157 
Reaping winning child 0x01a6de60 PID 6157 
Removing child 0x01a6de60 PID 6157 from chain.
Successfully remade target file `build'.

, : - ? ?

, Makefile , , , make. , : " ".

!

+3
5

:

my Makefile , , , make

.

Makefile:

CC = g++
FILES = makefile.cpp
OUT_EXE = makefileout

build: $(FILES)
    $(CC) -o $(OUT_EXE) $(FILES)

- build, ( , ). :

CC = g++
FILES = makefile.cpp
OUT_EXE = makefileout

${OUT_EXE}: $(FILES)
    $(CC) -o $(OUT_EXE) $(FILES)

make makefileout, build, .

, Makefile, :

rm -f makefileout
touch build
make

, , make . , () .

+1

"-d" "make". "-d" - , .

-d   Print debugging information in addition to normal processing.  The
     debugging information says which files are  being  considered  for
     remaking,  which  file-times  are  being  compared  and  with what
     results, which files actually need to be  remade,  which  implicit
     rules  are considered and which are applied---everything interest‐
     ing about how make decides what to do.

, -d, , .

+5

, -d. . , GNU make , , Makefile - . (, Ninja), , , .

+4

-d flag, , , .

0

make , . . https://www.gnu.org/software/make/manual/make.html#Implicit-Rules

, .SUFFIXES: make . , make, .

, .SUFFIXES:, - , Makefile git. .

- . -r --no-builtin-rules , .

0

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